Our studies are concerned with the induction, control, and function of the local secretory immune system in the genital tract. 1) We will study the role of local immunity in protecting the female genital tract against infectious agents by using ELISA to measure naturally occurring anti-bacterial antibodies in mouse vaginal fluid and anti-Salmonella antibodies after oral immunization with Salmonella. 2) We will use immunolabeling to quantitate IgA and IgG anti-ferritin plasma cells in four segments of the mouse female genital tract after ferritin immunization by several routes, including oral, vaginal, oral-vaginal, vaginal-vaginal, and intraperitoneal-vaginal. The results should clarify whether plasmablasts migrate from gut lymphoid tissue to the female genital tract. Also, the results would compare the effectiveness of primary immunizations at three sites in enhancing the local genital tract immune response to vaginal challenge. 3) Using adoptive transfer methods, we will localize radiolabeled plasmablasts in the female genital tract 24 hr after transfer of cells from mesenteric, combined iliac-renal, or peripheral lymph nodes. The comparison should determine whether there is selective homing to the genital tract by plasmablasts from local lymph nodes. The results from parts 2 and 3 should clarify the relationships of the local genital tract immune system to the common mucosal immune system. 4) We will use histological methods to describe the occurrence and distribution of lymphocyte-like cells in the epithelium and lamina propria of the rat oviduct, particularly the junctura, in relation to the time of mating. 5) We will study the local immune system of the male rat genital tract in two ways: by localizing IgA, IgG, and IgM plasma cells and secretory component in the genital tract with immunolabeling techniques, and by using ELISA to determine whether naturally occurring anti-bacterial antibodies are present in seminal fluid and whether anti-Salmonella antibodies can be detected in seminal fluid after oral immunization with Salmonella. Our objective is a better understanding of local immunity in the genital tract and its possible use in fertility control.